// mems.c -- using memcpy() and memmove()
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define SIZE 10
void show_array(const int ar[], int n);
// remove following if C11 _Static_assert not supported
_Static_assert(sizeof(double) == 2 * sizeof(int), "double not twice int size");
int main()
{
	int values[SIZE] = { 1,2,3,4,5,6,7,8,9,10 };
	int target[SIZE];
	double curious[SIZE / 2] = { 2.0, 2.0e5, 2.0e10, 2e20, 5.0e30 };

	puts("memcpy() used:");
	puts("values (original data): ");
	memcpy(target, values, SIZE * sizeof(int));
	puts("target (copy of values):");
	show_array(target, SIZE);

	puts("\nUsing memmove() with overlapping ranges:");
	memmove(values + 2, values, 5 * sizeof(int));
	puts("values -- elements 0-5 copied to 2-7:");
	show_array(values, SIZE);

	puts("\nUsing memcpy() to copy double to int:");
	memcpy(target, curious, (SIZE / 2) * sizeof(double));
	show_array(target, SIZE / 2);
	show_array(target + 5, SIZE / 2);

	return 0;
}

void show_array(const int ar[], int n)
{
	int i;
	for (i = 0; i < n; i++)
		printf("%d ", ar[i]);
	putchar('\n');
}